Advances in the 1990s

The 1990s saw the publication of several major reviews on the state of knowledge of Antarctic climate history, notably symposium volumes by Kennett and Warnke (1992, 1993), ANTOSTRAT monographs on the Ross Sea (Cooper, this volume) and in support of ODP drilling, three chapters in Tingey's (1991) monograph on the geology of Antarctica (Anderson, 1991; Denton et al., 1991; McKelvey, 1991) and the review of sedimentation on the Antarctic continental shelf by Hambrey et al. (1992). By now, the broad chronological framework had been established through drilling in McMurdo Sound (CIROS-1, Barrett, 1989) and in Prydz Bay (Barron, Larsen et al., 1989) on opposite sides of the continent. However, neither the earliest Oligocene onset of glaciation nor the middle Miocene transition had been sampled by drilling on the continental shelf, and progress was hampered by a lack of chronological tools comparable with those used to date deep-sea sediments (e.g. microfossil datums based on abundant rapidly evolving taxa integrated with magnetic reversal stratigraphy in continuous sedimentary sequences).

ANTOSTRAT contributed to a Detailed Planning Group of the ODP at College Station (TX) in 1994 for planning proposals for all five ANTOSTRAT sectors. However, in the event, only two legs were approved for drilling (Legs 178 in 1998 and Leg 188 in 2000). Both had some success in filling out the glacial chronology in each region in cores from fans and drifts on the slope and rise (Barker, Camerlenghi et al., 1999; O'Brien, Cooper et al., 2001; Cooper, this volume), though poor recovery marred the success of drilling on the continental shelf.

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